Radio antenna



J. B. CEJKA RADIO ANTENNA Nov. 4, 1958 2 Sheets-Sheet 1 Filed Nov. 20,1953 INVENTOR d05EP/r B CEJKA ATTORNEY$ J. B. CEJKA RADIO ANTENNA 2Sheets-Sheet 2 I Filed Nov. 20, 1953 FIG. 4.

z A M 8 M w Z 6 I 4 RE w 2 7 v a 4E I T w A H 2 N5 R 7 J 6 m 8 w o NH WW0 F F Mum United States Patent Office RADIO ANTENNA Joseph B. Cejka,Highland Park, N. J., assignor to General Bronze Corporation, GardenCity, N. Y., a corporation of New York Application November 20, 1953,Serial No. 393,331 7 Claims. (Cl. 174-153) 'This invention relates to animproved mounting device particularly useful as an integral part ofwhip-type radio antennas for automobiles.

There are a number of features that determine the suitability of anantenna for use on automobiles. Among these are: ease of mechanicalmounting, suitability for original installation at the automobilefactory or by an ordinary mechanic without special tools, suitability asa replacement unit in automobiles having antennas of other types,sturdiness of the mechanical mounting, the electrical characteristicssuch as are dependent upon capacity to the body of the automobile,corrosion resistance of the electrical connections and the like, and lowcost.

Unless an antenna is satisfactory in each of these respects, it will beof only limited utility. Many of the antennas proposed heretofore havesolved certain of these problems but in failing to meet one or more ofthe other requirements, have failed to provide the most satisfactoryanswer to the over-all problem.

In a preferred embodiment of the present invention, a pair of swingablymounted arms are mounted on the antenna base and are arranged whenparallel with the antenna to permit the base of the antenna to beinserted from the outside through an opening in the car body after whichthe arms are turned or swing naturally to a crosswise positionpermitting the antenna to be clamped in place by tightening a retainingnut against the outside of the body.

A pair of cam shoulders, preferably formed integrally with the antennabase, are positioned adjacent the arms tosupport the arms when theantenna is tightened in position.

The novel construction and arrangement of the electrical componentswithin the base of the antenna provide improved mechanical andelectrical characteristics and utilize fewer and lower cost parts thanother antenna arrangements. The construction of the antenna componentsis described more fully and is claimed in my copending application,Serial No. 393,333, filed on even date herewith, it being apparent thatthe mounting system described and claimed herein is not dependent uponthe use of any particular arrangement within the sleeve base of theantenna.

The various aspects, advantages, and features of this vention will be inpart pointed out in and in part apparent from the following descriptionof a preferred embodiment of the invention considered together with theaccompanying drawings, in which:

Figure 1 is a cross-sectional view of an antenna embodying the inventionshowing the antenna mounted on a portion of an automobile body;

Figure 2 is an expanded view showing the principal parts of the antennamounting structure;

Figure 3 is an enlarged partial elevational view of the antenna mountingstructure;

Figure 4 is a side view of the portion of the antenna shown in Figure 3;

7 opposite sides of the sleeve -die casting operation. The grooves 242,859,274 Patented Nov. 4, 1958 Figure 5 is a sectional view taken alongline 55 of Figure 3;

Figure 6 is a partial view similar to Figure 3 but with the anchor armsrotated so that the base can be inserted in the hole in the automobilebody;

Figure 7 is an enlarged partial side view showing a modification of theclamping structure; and

Figure 8 is an elevational view of the portion of the antenna mountingstructure shown in Figure 7.

In the embodiment of the invention shown in Figure l, thesignal-receiving portion 2 of the antenna, usually a telescoping tubeand rod assembly, is supported by a metal sleeve base 6 that extendsthrough and is secured to the sheet-metal body 8 of an automobile. Inorder to permit the antenna to be mounted conveniently from the outsideof the automobile, a pair of arms 10 and 12 (see also Figure 2) aremounted swingably on this sleeve so that the antenna can be insertedinto the opening in the body 8 and the arms turned crosswise to act asan anchor when the sleeve is secured in position by tightening a nut 14which is in threaded engagement with the sleeve 6.

In order to relieve the supports for the arms 10 and 12, in this exampleshown as projections 16 and 18 on 6, from the strain imposed when thenut 14 is tightened, the lower edges of the arms 10 and 12 are arranged,when the arms are turned crosswise, to abut, respectively, shoulders 20and 22 (Figure 4) on the sleeve 6. Thus, as the nut 14 is tightened thedownward deflection of the arms 10 and 12 is-limited by the engagementwith the shoulders 20 and 22 which bear the mechanical load and preventany possibility of shearing the projecting pivots 16 and 18.

In order to prevent the lower edges of the arms 10 and 12 from beingdeflected outwardly and sliding off their respective shoulders 20 and22, the surfaces of these shoulders form a slight angle, for examplefive degrees, with respect to a plane perpendicular to the longitudinalaxis of the antenna is indicated at a in Figure 4. That is, the surfacesof these shoulders extend downwardly and inwardly so that as the loweredges of the arms tend to move downwardly relatively to the sleeve 6they are carnmed inwardly.

In this particular example, the shoulder surfaces 20 and 22 are formedby grooves 24 and 26 in opposite sides of the sleeve 6, and each of thearms is provided with an arcuate inwardly-projecting flange, as at 28,which passes through the respective groove 24 or 26 when the arm isrotated. The lower surface of this flange, where it engages the surfaceof the cam shoulder, also forms a slight angle with the planeperpendicular to the longitudinal axis of the sleeve 6 in the samedirection as the shoulder. The flange thus seats or nests with theshoulder providing a somewhat increased bearing surface and furtherinsuring that the arms 10 and 12 will be held securely on the shoulders.

The sleeve 6 may be formed by die casting the pivots 16 and 18 and thegrooves 24 and 26 being formed by the and 26 are formed with curvedupper walls, the bottom surfaces 20 and 22 are nearly planar.

The arms 10 and 12 are formed of sheet steel or other suitably strongmaterial and may be of any desired shape so long as they aresufiiciently narrow to permit the antenna to be inserted through amounting hole of reasonable size when they are positioned along thelongitudinal axis of the sleeve and long enough to provide a good anchoragainst the inner surface of the automobile body when they are turnedcrosswise. The arcuate lower surface permitsthe necessary rotation ofthe arms and also provides a mechanically rigid structure when theantenna is tightened in position.

In order to mount the arms 10 and 12 on the projecting pivots 16 and 18,a metal eyelet, as at 3'0 and 32, is positioned loosely in a hole 34 ineach of the arms. A flange 35 rolled on the outer end of each eyelet(Figure 4) locks the arm and the eyelet together, but does not interferewith the free rotation of the arm relatively to the eyelet. Theeyelet-arm assemblies each are then placed on one of the pivots 16 or 18and the outer end of the pivot is then peened, as shown at 36 in Figure4, to secure the eyelet and arm in position. This construction permitsthe arms to be mounted rapidly and economically and insures that thearms will rotate freely so that afterthe antenna is inserted in themounting hole they will turn crosswise by the action of gravity alone,thus eliminating the need for manual manipulation of the arms after the.antenna is positioned in the mounting hole.

The holes 34- in the arms 1% and 12 are formed slightly larger than theouter diameters of the eyelets 3% and 32 'so that, as stated above, thearms fit loosely on the eyelets. This tolerance permits the flanges 23,or lower edges of the arms 10 and 12, to pass freely along the grooves24 and 26, but when the antenna is clamped in position 'by thetightening of the nut 14, the flange 28 abuts the shoulder on the sleeve6 and takes up the load without'placing significant strain on thearm-supporting pivots 16 and 18.

The die cast sleeve 6 is formed ordinarily of metal softer than that ofthe arms 10 and 12. The curved lower surface or flange 28 of the armstherefore tends to deform the shoulder somewhat as the nut 1 istightened to form a shallow indentation corresponding to the shape ofthe lower surface of the arm; the lost motion at the pivot beingsuflicient to permit such indentation without placing excessive strainon the pivots.

The lower length of tubing 37 of the telescoping assembly 2 is supportedby and insulated from the sleeve base 6. This is accomplished by abushing 38 of insulating material that fits within the upper portion ofthe sleeve 6. In this example, the sleeve or bushing 33 is formed ofpolystyrene, but other insulating materials can be used. The bushing ismolded in the shape best shown in Figures 1 and 2, with an externalannular shoulder near its lower end which, when the bushing is insertedin the metal supporting sleeve 6, abuts an internal annular shoulder, asat 42 in Figure l, on the sleeve 6. The tubing 37 fits snugly within theinsulation bushing 38 and extends into the bushing with its lower endabutting an internal shoulder 48 on the bushing 38.

In order to secure the insulating bushing 3% after it is inserted in thesleeve 6, the upper end of the sleeve 6 is rolled or swaged inwardly, asat 50, against a sloping annular shoulder 52 (Figure 2) on the outsideof the bushing 38 so that the bushing is firmly anchored between thelower shoulder 4-2 and the internal collar thus formed at the upper endof the sleeve 6.

The tubing 37 is secured in the insulation bushing 38 by a screw 54which is in threaded engagement with the inside wall of the tube 37, thehead of the screw being drawn up against a washer 56 that pressesagainst an internal shoulder 58 on the bushing 38.

The portion of the insulation bushing 38 below the washer 56 is providedto increase the length of the surface leakage path between the screw 54and the metal sleeve 6.

In order to permit electrical connection to be made to a plug 62 that isconnected by a shielded wire 64 to the radio receiver, the screw 54 isprovided with a longitudinal bore 66 in which is positioned a strip-likePhosphorbronze contact spring 6 3. the lower end to the outside of thehead of the screw 54 and extends upwardly within the bore 66. The spring68 is not secured inside the bore 66 but is pre-set with a number ofundulations along its length so as to insure goodcontact with thecentral conductor prong 70 of the This spring is spot welded at 4 plug62 which is adapted to be inserted through the bottom of the sleeve 6into the bore 66.

The ground connection between a spring metal sleeve 72 on the plug 62and the antenna sleeve 6 is completed by direct contact between thesleeve 72 and internal longitudinal projections 74 (Figure 5) on thesleeve 6.

Any suitable bushing arrangement may be used between the nut 14 and theouter surface of the automobile. For example, a conventional soft rubberprotecting and sealing washer 76 (Figures 1 and 2) may be placed aroundthe antenna adjacent the auto body. A slotted generally semi-sphericalinsulator 78, of acetobutyrate plastic such as is sold under thetrademark Tenite II, or other suitable material, is placed on top of thewasher 76 and is capped by a saucer-shaped washer oil against which thenut 14 is tightened. The washer 76, insulator 78, washer 80, and nut 14can all be constructed in accordance with prior art devices such as arealready in Wide use.

From the foregoing, it will be observed that the antenna described aboveand embodying the present invention is well adapted to meet the ends andobjects set forth above and to be manufacturedeconomically, thestructure being formed of relatively few parts and these being such thatthey can be produced by well-known low-cost production techniques.

It will be apparent that various modifications of the individualfeatures can be made without departing from the scope of the inventionin order to best adapt the invention to a particular use orconstructional technique. For example, an external shoulder 32,corresponding to the shoulders 26 and 22, can be formed, as shown inFigure 7, by abruptly increasing the outer diameter of the sleeve 6. Theinwardly projecting flange 28 can be eliminated from the arms 10 and 12to form arms 84. As shown in Figure 8 the extent of rotation of the arms84- is more limited than in the-earlier embodiment so that a largeropening is required for mounting the antenna. The remaining parts of theantenna are similar to those described in connection with the antenna ofFigures 1 to 6, corresponding parts being indicated by the same numeralsfollowed by the suflix A.

What is claimed is:

1. An automobile antenna structure including an elongatedelectrically-conductive signal-receiving member, a

mounting sleeve mechanically supporting said signalreceiving member andhaving at opposite sides flattened faces with a pair of studs formedintegrally with said sleeve and projecting perpendicularly from saidflat faces, a pair of swingably-mo-unted arms loosely supported by saidstuds on said sleeve, arcuate grooves formed in said flat facesconcentrically with said studs, and arcuate flanges on said armsslidably received in said grooves, said flanges engaging the Walls ofsaid grooves when said arms are turned substantially crosswise of saidsleeve-so as to provide support for said arms when the antenna isclamped in position on an automobile.

2. An automobile antenna structure including an elongatedelectrically-conductive signal-receiving member, a mounting sleevemechanically supporting said signal-receiving member, a pair ofswingably-mounteda-rms supported by said sleeve, and shoulder meanssupported by said sleeve and having a shoulder surface sloping in-"wardly and downwardly and positioned respectively to abut said swingablearm when the arm is turned substantially crosswise of said sleeve, thelower surface of said arm adjacent said shoulder surface slopinginwardly and downwardly in the same direction as said shoulder surfacewhen in its crosswise position.

3. An automobile antenna structure including an elongatedelectrically-conductive signal-receiving member, a mounting sleeve,means'secured to the outer endof said sleeve and mechanically supportingsaid signal-receiving member in electrically insulated relation to saidsleeve, an electrical conductor extending axially through said sleeve ininsulated relation thereto for making electrical connection to saidsignal receiving member, a pair of swingably-mounted arms supported bypivots extending outwardly from opposite sides of said sleeve and havingflanges extending inwardly thereof, and shoulder means formed at theouter surface of said sleeve by oppositelydisposed grooves on saidsleeve and having two surfaces positioned respectively to abut one ofsaid flanges of the swingable arms when the arm is turned substantiallycrosswise of said sleeve, whereby to provide support for the arms whenthe antenna is clamped in position on an automobile.

4. An automobile antenna structure including an elon gatedelectrically-conductive signal-receiving member, a mounting sleevemechanically supporting said signal-receiving member, a pair ofswingably mounted arms supported by pivots extending outwardly fromopposite sides of said sleeve and having arcuate flanges extendinginwardly along an edge thereof, and shoulder means formed at the outersurface of said sleeve by oppositely-disposed grooves on said sleeve,said grooves having abutment surfaces positioned to abut said flangeswhen the arms are turned crosswise of the sleeve, said surfacesextending, in the area of contact with said flanges, at an angle to aplane perpendicular to the longitudinal axis of said sleeve.

5. An automobile antenna structure as claimed in claim 4 wherein saidangle between said abutment surfaces and said plane perpendicular to thelongitudinal axis of said sleeve is about five degrees.

6. In an automobile antenna, a signal-receiving portion, anantenna-supporting sleeve for supporting said signal-receiving portionadapted to extend through a hole in the body of an automobile and havinga pair of oppositely-disposed externally-projecting pivots, said sleevehaving a pair of grooves formed in the external surface thereofrespectively beneath said pivots, and a pair of antenna-anchoring armseach swingably mounted on one of said pivots and each having an arcuateinwardlyextending flange arranged to traverse one of said grooves andupon installation of the antenna to be placed in pressure contact withthe lower wall thereof, each of said arms having suflicient lost motionwith respect to the pivot upon which it is mounted to permit said flangethereof to freely traverse its respective grooves and to make pressurecontact with one wall thereof without placing substantial strain on theprojecting pivot supporting the arm.

7. An automobile antenna including a telescoping rod and tube assemblyfor receiving radio signals, a tubular base for supporting said rod andtube assembly, said base being a malleable die casting and having a pairof integrally cast pivot means projecting from opposite sides of saidbase, and a pair of opposed shoulder surfaces adjacent said pivots andaligned generally perpendicularly to the direction of said pivot, a pairof elongated anchoring arms each having a hole therein and each havingan arcuate projecting surface concentric with the adjacent pivotarranged to abut one of said shoulders, and a pair of eyelets eachpositioned loosely in one of the holes in the anchoring arms, each ofthe eyelets being positioned on one of said pivot means, said pivotmeans being swaged and thereby locking said eyelet in position, saidholes being sufficiently larger than said eyelets to permit said arcuatesurfaces to bear against said shoulders without substantial strain onsaid pivots.

References Cited in the file of this patent UNITED STATES PATENTS594,043 Thompson et al. Nov. 23, 1897 2,509,563 Grashow May 30, 19502,578,515 Crafton Dec. 11, 1951

